This worksheet provides six challenging problems that will involve learners using Pythagoras' Theorem to find missing lenghts of 3D shapes. The shapes in this worksheet consist of cuboids, cubes, triangular prisms and a square based pyramid. Some of the questions als0 involve the volume of the shape so learners may need to know the volume formulae and be able to work backwards if given the volume. You csan find more questions in 3D Pythagoras (B).